The fabrication of microelectronic components from a workpiece, such as a semiconductor wafer substrate, polymer substrate, etc., involves a substantial number of processes. There are a number of different processing operations performed on the workpiece to fabricate the microelectronic component(s). Such operations include, for example, material deposition, patterning, doping, chemical mechanical polishing, electropolishing, and heat treatment.
Material deposition processing involves depositing thin layers of electronic material to the surface of the workpiece (hereinafter described as, but not limited to, a semiconductor wafer). Patterning provides removal of selected portions of these added layers. Doping of the semiconductor wafer is the process of adding impurities known as “dopants” to the selected portions of the wafer to after the electrical characteristics of the substrate material. Heat treatment of the semiconductor wafer involves heating and/or cooling the wafer to achieve specific process results. Chemical mechanical polishing involves the removal of material through a combined chemical/mechanical process while electropolishing involves the removal of material from a workpiece surface using electrochemical reactions.
Numerous processing devices, known as processing “tools”, have been developed to implement the foregoing processing operations. These tools take on different configurations depending on the type of workpiece used in the fabrication process and the process or processes executed by the tool. One tool configuration, known as the Equinox(R) wet processing tool and available from Semitool, Inc., of Kalispell, Mont., includes one or more workpiece processing stations that utilize a workpiece holder and a process bowl or container for implementing wet processing operations. Such wet processing operations include electroplating, etching, cleaning, electroless deposition, electropolishing, etc.
In accordance with one configuration of the foregoing Equinox(R) tool, the workpiece holder and the process bowl are disposed proximate one another and function to bring the semiconductor wafer held by the workpiece holder into contact with a processing fluid disposed in the process bowl and forming a processing chamber.
Conventional workpiece processors have utilized various techniques to bring the processing fluid into contact with the surface of the workpiece in a controlled manner. For example, the processing fluid may be brought into contact with the surface of the workpiece using a controlled spray. In other types of processes, such as in partial or full immersion processing, the processing fluid resides in a bath and at least one surface of the workpiece is brought into contact with or below the surface of the processing fluid.